JPS6260605A - Seal structure of formwork for molding concrete pipe - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION <Field of Industrial Application> The present invention relates to a sealing structure for concrete 1 to split formwork for pipe forming.

<Conventional technology and problems> The formwork used for centrifugal force forming of concrete 1 to pipes includes the V1 formwork, which is a combination of a pair of single formworks, and the seamless formwork, which is an integrated seamless formwork. Formwork is used.

The former type of split formwork has a flange on the outer surface of the joint part of the side formwork, and this flange is connected with bolts and nuts, so when the formwork is assembled, there is a flange at the flange joint. There is a problem in that gaps are formed and paste flows out from the gaps during concrete pipe forming, degrading the quality of the product.

For this reason, the current practice for split formwork is to clean the abutting surfaces of the flanges each time the formwork is used, and to apply tape to the inner surfaces of the joints after assembling the formwork to improve the sealing performance of the joints. be.

Furthermore, although the latter seamless formwork does not have any of the problems that occur at the joints of the split formworks, it does have the problem of not being able to form chemical prestressed concrete pipes.

In other words, chemical prestressed concrete pipes are formed by mixing an expanding agent into the concrete material, so the press of the concrete is applied in the radial direction of the formwork during forming, causing the product to be removed from the formwork. You will not be able to do so.

In this way, in order to manufacture chemically prestressed concrete pipes, it is necessary to use a split formwork due to the problem of demolding, and it is desirable to solve the problem of the joints that occur in the split formwork. The current situation is that

This invention was made in view of the above-mentioned points9, and it provides a concrete pipe that can reliably seal the seams of split formwork and can greatly reduce the need for one lifting operation when using the formwork. The purpose of the present invention is to provide a sealing structure for a molding frame.

Means for Solving the Problems> In order to solve the above problems, the present invention forms the sealing material into a cross-sectional shape with mounting portions provided at both ends of the expandable portion, and the sealing material is divided into two parts. The expandable part is installed between the joints of the split formwork so that it matches the inner peripheral surface of the formwork, and both mounting parts are fixed to the flanges of the formwork joint using mounting brackets. .

<Function> When assembling the split formwork, the mounting brackets abut each other and the elastic part of the sealing material extends along the inner surface of the formwork, and this elastic part becomes part of the molding surface. .

Forming a concrete pipe - When demolding later, the joints at the seams are uncoupled and pushed open, and the expandable part of the sealing material is stretched, allowing the upper and lower formwork to separate into upper and lower parts while remaining sealed. The internal concrete pipe can be demolded.

<Example> Hereinafter, an example of the present invention will be described based on the accompanying drawings.

As shown in the figure, the formwork 1 is formed into two V] by a pair of formwork units 2 and 2, and the joint parts on both sides of the circular formwork unit 2.2 are such that one side is fixed and the other side is Becomes the opening/closing side,
The fixed side is a flange 3 installed on the outer surface of the single circular frame 2.2.
．． 3 are connected with lock pins or bolts, and serve as a supporting part when the formwork 2.2 is opened and closed.

The sealing material 4 used on the opening/closing side has a cross-sectional shape with attachment parts 6.6 connected to both ends of the elastic part 50, and this sealing material 4 is made of rubber or synthetic resin with excellent alkali resistance. The portion 5 is made of a soft material, and both mounting portions 6.6 are made of a hard material.

The opening/closing part of the single circular frame 2.2 has a flange 7 on its outer surface.
7 is fixed, and the sealing material 4 is interposed between the opposing faces of both flanges 7.7, so that the end face of the expandable part 5 is an extension of the same surface as the inner surface of the formwork unit 2.2. 6 is fixed to the flange 7.7 with a mounting bracket 8.8.

The mounting fitting 8 is formed by a combination of a mouth-shaped fitting main body 8a that fits over the flange 7 and the mounting part 6, and a bolt 8b that is screwed into the fitting main body 8a to fix the flange 7 and the mounting part 6. , the two-piece fitting 8.8 is formed by assembling the formwork units 2 and 2, so that the fitting bodies 8 and 8 abut each other, and the flange 7.7
By maintaining a predetermined interval between them, the elastic part 5 is prevented from being deformed due to unnecessary compression, and therefore the elastic part 5 constitutes a part of the concrete pipe forming surface. .

In addition, the circular frames 2 and 2 may be opened and closed by connecting the flanges 7.7 with bolts and nuts, but for example, as shown in Fig. 4, one flange may be penetrated and fixed to the other flange. One end of a clamp lever 10, which is pivoted on one flange, is connected to the bolt 9, and the tension bar 11, which is connected to the other end of the clamp lever 10, is moved in the longitudinal direction to swing the clamp lever 10. A one-touch structure for opening and closing the unit 2.2 may be adopted.

The sealing structure of the present invention has the above-mentioned configuration, and when the formwork units 2.2 are joined together to form the concrete pipe lλ, the mounting fittings 8.8 are brought into contact with each other as shown in FIG. The sealing material 4 seals the seam part of the joint part, and the expandable part 5 becomes the molding surface of the concrete pipe A.

To remove the concrete pipe A, all you have to do is release the coupling mechanism of the opening/closing side joint and pull up the formwork unit 2 in the lower position relative to the lower formwork unit 2, as shown in Figure 3. ,
The flanges 7.7 are separated, the sealing material 4 moves up and down, the telescopic part 5 extends, and the upper formwork unit 2 moves from concrete 1 to pipe A.
Even if concrete pipe A is a chemical prestressed pipe, it can be removed from the mold.

After demolding, even if the formwork unit 2.2 is separated, the sealing material 4 seals the seam of the joint part.
There is no need to clean the seams when cleaning the inside of the formwork.

According to the present invention, the sealing material is formed into a cross-sectional shape with mounting portions provided at both ends of the expandable portion, and this sealing material is attached to the flange of the frame center body using the mounting bracket “C”. Installed between ε,
Since the expandable part is aligned with the inner peripheral surface of the single formwork, it is possible to seal the joint-V part of the joint part that goes into the two-part structure, and there is no paste leakage during concrete 1 to pipe forming. , it is possible to manufacture concrete pipes with high precision.

In addition, the elastic part of the seal material becomes the molding surface of the concrete pipe, and the elastic part expands when the two-split formwork is opened, so the formwork can be opened without any trouble and the concrete pipe can be formed smoothly with high precision. It is possible to produce high-quality chemical press 1-less concrete pipes that can be demolded.

Furthermore, since the joint part of the two-split formwork is sealed with a sealant, there is no leakage of concrete paste into the joint part, and there is no need to clean the joint part when cleaning the inside of the formwork. This saves labor in cleaning the formwork.

[Brief explanation of the drawing]

Fig. 1 is a sectional view of a mold using the seal structure according to the present invention, Fig. 2 is an enlarged sectional view of the main parts of the same, Fig. 3 is a sectional view showing the same as the above in a demolded state, and Fig. 4. is a front view of the formwork. 1... Formwork 2... Formwork alone 4... Seal material 5... Expandable part 6... Mounting part
7...Flange 8...Mounting bracket Patent attorney Kazu 1) Showa 1, 2, 3, 4

Claims (3)

[Claims] (1) The sealing material is formed into a U-shaped cross section with attachment parts provided at both ends of the expandable part, and this sealing material is placed between the seams of the joint parts of the two-split formwork so that the expandable part is attached to the inner periphery of the formwork. A sealing structure for a formwork for forming concrete pipes, which is assembled so that it matches the surface, and both mounting parts are fixed to the flanges of the formwork joint part using mounting brackets. (2) The sealing structure for a formwork for forming a concrete pipe according to claim 1, wherein the sealing material is formed using a soft material for the expandable portion and a hard material for the attachment portion. (3) In the formwork for forming concrete pipes according to claim 1, the mounting fittings are adapted to abut against each other when the formworks are assembled to maintain a constant gap between the joint parts. Seal structure.